Aromatic, aliphatic, alicyclic and aromatic heterocyclic amine-boranes are useful as reducing agents for various substrates, in reductive amination reactions, in the hydroboration of alkenes and alkynes, in procedures for the electroless plating of metals and in the synthesis of ceramic and preceramic materials.
Of particular importance in the context of this invention is the fact that pyridine-borane is a key reagent in the synthesis of zileuton [N-1(1-benzo[b]thien-2-ylethyl)-N-hydroxyurea] ##STR1##
Zileuton is a 5-lipoxygenase inhibitor devoid of cyclooxygenase and 12- and 15-lipoxygenase inhibitory activity. See, e.g., DN&P 4(1):46 et. seq. Pyridine-borane is used in the penultimate step of zileuton synthesis as shown by the following Equation I: ##STR2##